JP7450673B2 - Hydrophobic filters for filtering air or other gas streams in medical applications - Google Patents

Description

explanation

The present invention relates to a hydrophobic filter for filtering air or other gas flows in medical applications according to the preamble of claim 1.

Hydrophobic filters of this type include a housing surrounding a filter chamber, an inlet port disposed on the housing forming an inlet opening, an outlet port disposed on the housing forming an outlet opening, and an elongated a porous filtration medium including a hydrophobic structure of a hydrophobic membrane extending along a surface and separating the filter chamber into an inlet chamber and an outlet chamber, an inlet opening opening into the inlet chamber and an outlet opening opening into the inlet chamber; It opens into the exit chamber.

Hydrophobic filters of this type may be used, for example, in conjunction with autotransfusion systems. Herein, blood is collected into the reservoir using a negative pressure pump, e.g., a vacuum pump, by creating a negative pressure in the reservoir with the pump and drawing blood into the reservoir from the patient's surgical site. can do. The hydrophobic filter herein is a negative pressure line that connects the reservoir to the pump to avoid liquid and debris being carried towards the pump, prevent damage to the pump, and direct air flow towards the pump. used above.

In operation, air is drawn through the filter, which enters the filter chamber through the inlet port, passes through a hydrophobic structure, for example in the form of a membrane, and passes through the outlet port towards the pump and into the filter chamber. get out of Hydrophobic structures are designed to allow air or other gases to pass through, but prevent water or other aqueous solutions from passing through the structure. The airflow is therefore filtered to prevent liquids or debris from entering the pump.

During surgery, autotransfusion systems may be used continuously for several hours. During long-term operation, condensation may occur within the hydrophobic filter and condensate (and other liquids or particles, hereinafter simply referred to as condensate) may collect in the inlet chamber of the filter. If such condensate fills the inlet chamber to a significant extent, the condensate can prevent air from passing through the filter and can act like a plug preventing further use of the filter. If this occurs during surgery, it may be necessary to replace the filter, but this should be avoided.

The aim of the invention is to provide a hydrophobic filter that remains usable despite the possibility of condensate forming in the inlet chamber.

This object is achieved by a filter comprising the features of claim 1.

Accordingly, the outlet opening opens into the outlet chamber at a first position when viewed along the extension plane, and the inlet opening opens into the outlet chamber at a second position different from the first position when viewed along the extension plane. It opens into the filter chamber at the position.

In particular, the housing includes a bottom and a top, and the second position is displaced toward the top with respect to the first position.

For example, when used in an autotransfusion system, the filter is connected to the system at a defined location, for example, with the bottom of the filter housing being located lower than the top. The inlet opening opens into the inlet chamber at a second position displaced towards the top with respect to the first position, so that air enters the inlet chamber through the inlet opening and the hydrophobic The condensed liquid collects in the inlet chamber below the inlet opening, so that despite the collection of condensate in the inlet chamber, the condensed liquid does not prevent the flow of the condensed liquid through the filtration media provided with the structure and into the outlet chamber. , the filter continues to function.

In one embodiment, the first location may be aligned with a location where the axis of symmetry intersects the extended surface of the hydrophobic structure. The second position is offset with respect to the first position when viewed along the extension surface, particularly towards the top.

By having the inlet opening enter the inlet chamber at a different location (as viewed along the extended surface of the hydrophobic structure) than the location at which the outlet opening opens into the outlet chamber, the filter The design may be such that a certain amount of condensate can collect in the inlet chamber before disturbance occurs. In particular, the inlet chamber may be designed such that the volume available within the inlet chamber for collecting condensate is sufficient to receive condensate in amounts that can be reasonably expected over a long period of surgery. .

In another aspect, the inlet chamber can be designed to form a collection chamber suitable for collecting a significant amount of condensate in the bottom region of the housing.

In a first embodiment, the inlet chamber may include a tapered structure that tapers away from the hydrophobic structure, the tapered structure forming a collection chamber. The tapered structure may be shaped, for example, pyramidal or conical (with the conical axis perpendicular to the extended plane of the hydrophobic structure) so that the inlet chamber contains a volume large enough to collect a significant amount of condensate. oriented conical shape). The tapered structure allows condensate to collect at the bottom of the inlet chamber without occluding a substantial area of the hydrophobic structure and thus without substantially affecting the filtration performance of the hydrophobic filter. It serves to increase the volume of the inlet chamber.

In one embodiment, the inlet chamber can include an inlet structure adjacent to the tapered structure on the side facing away from the hydrophobic structure. An inlet port herein is defined, for example, as being formed on the inlet structure and opening into the inlet chamber at a location substantially (along a direction perpendicular to the extension surface) away from the hydrophobic structure; The body may be configured to advantageously allow air to flow, eg, to efficiently pass through the hydrophobic structure of the membrane towards the exit port.

In one embodiment, the inlet structure can include a curved guide surface configured to guide air into the inlet chamber. The flat surface extends at an angle of, for example, 90° to the guide surface, and the inlet port is arranged on the flat surface. Thus, air entering the inlet chamber through the inlet port impinges on the guide surface and is guided by the guide surface towards the hydrophobic structure, resulting in a beneficial flow towards the hydrophobic structure.

In another embodiment, the inlet chamber can widen toward the bottom to form a collection chamber near the bottom. For example, when viewed in a vertical section (from bottom to top) perpendicular to the extended plane of the hydrophobic structure, the inlet chamber can have a polygonal shape, and the rear wall of the housing (on the opposite side of the structure) , tapering toward the top such that the inlet chamber at the bottom of the housing is substantially wider than the top of the housing. In this way, a significant volume is formed at the bottom of the housing on the side of the inlet chamber, such volume being suitable for collecting a significant amount of condensate.

In another embodiment, the collection chamber may be formed on the side of the inlet chamber such that it extends below the bottom end of the hydrophobic structure. Therefore, the condensate is collected in the collection chamber below the hydrophobic structure so that during operation of the filter the condensate does not block the substantial area of the hydrophobic structure and therefore does not affect the filtration performance. can do.

In another aspect, a drainage port may be provided in the inlet chamber. A drainage port may be formed, in particular in the region of the bottom of the housing, so that condensate can be drawn out from the inlet chamber. By draining condensate from the inlet chamber, filtration performance can be maintained in that condensate can be removed from the inlet chamber at the same time that a significant amount of condensate has collected in the inlet chamber.

In another aspect, the outlet opening is in the form of a groove along the horizontal direction oriented perpendicularly to the extending surface to guide the air flow or another gas flow from the filter chamber along the horizontal direction. can be extended. Air thus leaves the filter chamber along the horizontal direction perpendicular to the extension plane and thus along the direction in which the air passes through the hydrophobic structure, for example in the form of a membrane. It may be provided here that the inlet opening extends in the form of a groove along a vertical direction oriented parallel to the extension plane and thus transversely to the horizontal direction. Air is therefore guided into the inlet chamber along a direction different from the horizontal direction. This can be beneficial, on the one hand, to guide the air into the inlet chamber of the filter so that the liquid and particles carried with the air collect at the bottom of the inlet chamber. This may also be beneficial in order to be able to properly lay a line between the reservoir and the filter to collect blood in the context of an autotransfusion system.

The housing may be formed by two separate housing members connected to each other, for example by welding, and retaining the hydrophobic structure between them. The inlet port may be located, for example, in the first housing member and the outlet port is located in the second housing member. The hydrophobic structure, for example in the form of a membrane, is arranged between a first clamping part of the first housing member and a second clamping part of the second housing member such that the structure is held between the housing members by the clamp. It may be sandwiched between. The clamping portion of the first housing member or the second housing member is attached to the periphery of the first housing member or the second housing member such that the hydrophobic structure is retained between the housing members along the circumference thereof. Extends circumferentially along.

In addition to the clamp, the hydrophobic structure can be welded to the first housing member and/or the second housing member.

In another aspect, the first housing member may include a first support structure formed by a plurality of ridges. The ridge may, for example, extend transversely to the extended surface of the hydrophobic structure and may project from the rear wall of the first housing member towards the hydrophobic structure.

Similarly, the second housing member can include a second support structure formed by a number of ridges, the ridges extending transversely to the elongated surface of the hydrophobic structure, for example; Projecting from the rear wall of the second housing member toward the hydrophobic structure.

Each support structure is suitable for supporting the hydrophobic structure against excessive deformation to prevent tearing of the structure.

In particular, the first support structure of the first housing member supports the hydrophobic structure when an opposing suction force is created on the hydrophobic structure toward the inlet port. When such an attractive force is generated, the hydrophobic structure comes into contact with the first support structure, and excessive deformation of the hydrophobic structure is prevented.

The second support structure of the second housing member then serves to prevent excessive deformation of the hydrophobic structure toward the outlet opening during normal operation of the filter. In particular, when a suction force is present on the outlet port, the hydrophobic structure may abut the second support structure such that excessive deformation of the hydrophobic structure towards the outlet opening is prevented. be.

In another aspect, in addition to or in place of the second support structure, at least one support member may extend across the outlet opening. The at least one support member can, for example, have the shape of a beam extending across the outlet opening (formed by the groove for conducting air from the outlet chamber) parallel to the extension surface of the hydrophobic structure. For example, in one embodiment, a number of beam-shaped support members may extend across the exit opening and may intersect with each other such that a crossing structure is formed across the exit opening. In this way, excessive deformation of the hydrophobic structure at the location of the outlet opening can be prevented, and the hydrophobic structure is supported at the location of the outlet opening by one or more support members. The at least one support member provides additional support for the hydrophobic structure at the location of the exit opening, thus reducing the risk of tearing of the hydrophobic structure at the location of the exit opening. .

The provision of at least one support member extending across the outlet opening may represent an original concept that may be used on its own.

In particular, a hydrophobic filter for filtering an air stream or other gas stream in medical applications includes a housing surrounding a filter chamber, an inlet port disposed on the housing and forming an inlet opening, and an inlet port disposed on the housing. and a hydrophobic structure extending along the extending surface to divide the filter chamber into an inlet chamber and an outlet chamber, the inlet port opening into the inlet chamber and the outlet port opening into the outlet chamber. . As used herein, the filter includes at least one support member extending across the outlet opening.

The filters described above may be suitably combined with some or all of the features as described above.

In one embodiment, the outlet opening may be tapered in the direction toward the hydrophobic structure. Generally, the housing member forming the housing of the filter can be formed from a suitable plastic material, for example as a rigid part, using molding techniques such as injection molding techniques. wherein, during the manufacture of the second housing member, during assembly of the filter, in order to make it possible to manufacture at least one support member in a position where the outlet opening of the second housing member opens into the outlet chamber; An outlet opening (of the outlet chamber) having a conical shape such that the forming tool can be removed from the second housing part in a direction facing away from the side of the second housing part in which the hydrophobic structure is to be placed. (forming a groove for guiding the flow to the outside) can be provided. This makes it possible to form the at least one support member across the outlet opening by injection molding when manufacturing the second housing member. The inverted conical nature allows for injection molding of the second housing member, including forming at least one support member across the outlet opening.

The hydrophobic filter described above may be used, for example, in an autotransfusion system to collect blood from a patient's surgical site to process the blood for reinfusion. However, hydrophobic filters may also be used in other medical applications where air or other gas streams may be filtered.

In one embodiment, the filtration media is a sheet manufactured from a single layer or from a stack of multiple layers of the same or different materials, e.g. in the form of a membrane or any other porous structure. may include a porous fabric. Hydrophobic structures may be made from any suitable material known in the art. The hydrophobic filter cloth can be made, for example, from PTFE material, but other materials are also conceivable.

Hydrophobicity in the present context is to be understood as the tendency of a filtration medium to adsorb little or no water. Hydrophilic filtration media exhibit an affinity for water and readily adsorb water, whereas hydrophobic filtration media have an opposite response to water interactions compared to hydrophilic substances. Hydrophobic materials have little or no tendency to adsorb water, and water tends to bead up (i.e., form discrete droplets) on their surface. Hydrophobic materials generally have low surface tension values and lack active groups in their surface chemistry for the formation of "hydrogen bonds" with water. Therefore, water or other aqueous solutions generally cannot pass through the hydrophobic structure of the filtration media, so water or other aqueous solutions, even debris particles, etc., are blocked by the filter, and air or other gas streams are not filtered. Ru.

The concept underlying the invention will be explained in more detail below with reference to the embodiments shown in the drawings.

FIG. 1 is a diagram showing a schematic diagram of an autotransfusion system.
FIG. 2 shows a diagram of a first embodiment of a hydrophobic filter.
FIG. 3 shows another view of an embodiment of a hydrophobic filter.
FIG. 4 is a diagram showing a cross-sectional view of the housing member of the hydrophobic filter.
FIG. 5 shows a view inside the first housing member of the hydrophobic filter.
FIG. 6 shows a view inside the second housing member of the hydrophobic filter.
FIG. 7 is a diagram showing a schematic diagram of a mold for forming a second housing member of a hydrophobic filter.
FIG. 8 shows a schematic diagram of another embodiment of a hydrophobic filter.
9 shows a cross-sectional view of the filter according to FIG. 8; FIG.
FIG. 10 is a diagram showing a schematic cross-sectional view of another embodiment of a hydrophobic filter.
FIG. 11 shows a schematic diagram of another embodiment of a hydrophobic filter.
FIG. 12 is a diagram showing a schematic diagram of yet another embodiment of a hydrophobic filter.
FIG. 13 shows a hydrophobic filter known in the art.
FIG. 14 shows a cross-sectional view of the filter according to FIG. 13.

FIG. 1 shows a schematic diagram of an autotransfusion system 5 configured to draw blood L from a reservoir 2 in order to process the blood for reinfusion into a patient, for example during surgery.

Within the embodiment of FIG. 1, blood L can be drawn into the reservoir 2 from the patient's surgical site via line 200, for example. By means of the line 50, the blood L collected in the reservoir 2 can be continuously drawn into the separation washing chamber 51, where it is necessary to obtain a packed concentration of red blood cells for reinfusion into the patient via the line 52. Second, unnecessary components are removed from the blood L. Blood transfusions may be performed continuously such that blood L is continuously collected from the patient and continuously processed to reinfuse the processed blood components into the patient.

The line 200 is connected to an inlet 20 located on the housing 22 of the reservoir 2. By creating a negative pressure within the housing 22 of the reservoir 2, a liquid flow F is drawn into the reservoir 2, thereby drawing an air flow A or another gas flow (hereinafter collectively referred to as air flow) into the port 22 of the housing 22. is drawn from the housing 22 by a line 210 connected to the housing 22. The air flow A is caused by a negative pressure pump 3, for example configured as a vacuum pump, which passes from the housing 22 through a line 210, through the filter 1 connected to the line 210, and between the filter 1 and the pump. 3 through a line 30 extending between 3 and 3.

Pump 3 serves to suck air from housing 22. In order to prevent liquids or debris from being drawn towards the pump 3 along with the air flow A, the filter 1 is fitted with a hydrophobic membrane 12 (hereinafter abbreviated as hydrophobic) which separates the filter chamber 130 into an inlet chamber 133 and an outlet chamber 134. The filter is configured as a hydrophobic filter with a filtration medium that includes a hydrophobic structure of a hydrophobic membrane. An inlet port 10 is arranged on the housing 13 of the filter 1 and opens into an inlet chamber 133, whereas an outlet port 11 arranged on the housing 13 emerges from an outlet chamber 134. Line 210 is in fluid communication with inlet port 10, whereas line 30 extending towards pump 3 is in fluid connection with outlet port 11.

During operation, airflow A is continuously drawn through filter 1. Here, condensate C may occur in the inlet chamber 133 due to condensation appearing in the inlet chamber 133 and liquid and debris drawn towards the filter 1 flowing in the line 210 with the air flow A. However, due to the hydrophobic nature of the membrane 12, liquid and debris may not pass through the liquid 12 but remain within the inlet chamber 133. Only air is drawn through the membrane 12 and thus filtered so that no liquid or debris flows towards the pump 3.

As shown in FIGS. 13 and 14, the conventional filter 1 can have a circular shape (FIG. 13), with the inlet port 10 and the outlet port 11 being centered with respect to the extended surface E along which the hydrophobic membrane 12 extends. aligned with each other in position. When condensate C accumulates within inlet chamber 133 and eventually reaches a position where inlet port 10 opens into inlet chamber 133, condensate C prevents air from flowing through membrane 12, resulting in an efficient Acts as a plug to prevent filtration. This can pose a problem during surgical procedures, particularly if the surgical procedure lasts for an extended period of time (eg, several hours) and the autologous blood transfusion system is to be used continuously during the procedure.

It is therefore desirable to prevent condensate C from interfering with the filtration operation and blocking a significant portion of the hydrophobic membrane 12, which could otherwise affect filtration performance.

In the embodiment of the hydrophobic filter 1 shown in FIGS. 2 to 6, the housing 13 of the filter 1 is connected to each other along connecting structures 140, 150 that extend circumferentially around each housing member 14, 15. It is formed from two housing members 14,15. The housing parts 14, 15 may be fixed to each other, for example by gluing or welding. Radially inwardly of the connecting structures 140, 115, each housing member 14, 15 includes a clamping portion 141, 151 extending circumferentially around the housing member 14, 15, the clamping portion 141, 151 having a Configured to receive a hydrophobic membrane 12 . The hydrophobic membrane 12 is held in a clamping manner between the housing parts 14, 15 when the housing parts 14, 15 are assembled to form the filter 1. In the assembled state, the hydrophobic membrane 12 separates the filter chamber 130 inside the housing 13 into an inlet chamber 133 and an outlet chamber 134 .

Inlet port 10 is located on inlet structure 144 adjacent tapered structure 143 of housing member 14 . The inlet port 10 has an inlet opening 100 in the form of a groove opening to the inlet chamber 133 such that airflow A can enter the inlet chamber 133 through the inlet port 10 and flow toward the hydrophobic membrane 12. form. As is clear from FIG. 2, the tapered structure 143 has a pyramid shape that tapers away from the hydrophobic membrane 12. The inlet structure 144 adjacent to the tapered structure 143 includes a guide surface 144A having a curved shape, and the inlet port 10 is disposed on a flat surface 144B disposed at an angle of approximately 90° with respect to the guide surface 144A. Ru. The inlet opening 100 extends along the vertical direction V (see FIG. 4) parallel to the extended surface E of the hydrophobic membrane 12, so that the airflow A passes through the inlet opening 100 in the vertical direction V to the inlet. It is guided into the chamber 133 and guided toward the hydrophobic membrane 12 by the curved guide surface 144A.

The outlet port 11 of the housing member 15 has an outlet opening 100 in the form of a groove which is centrally arranged with respect to the hydrophobic membrane 12 and extends along a horizontal direction H perpendicular to the extended plane E of the hydrophobic membrane 12. form. The air that has passed through the hydrophobic membrane 12 thus passes through the outlet opening 110 along the horizontal direction H towards the pump 3 connected to the outlet port 11 by a line 30, as schematically shown in FIG. from the outlet chamber 134.

As seen in FIG. 4, the inlet opening 100 enters the inlet chamber 133 in a position displaced towards the top 132 of the filter 1 with respect to the outlet opening 110. The filter 1 is now placed in position on the autotransfusion system 5 such that the hydrophobic membrane 12 is arranged vertically and the bottom 131 of the housing 13 is located downwardly with respect to the top 132 of the housing 13. Please note that.

Since the inlet opening 100 extends along the vertical direction V, air is guided into the inlet chamber 133 in an advantageous manner so that the condensate C collects at the bottom 131 within the inlet chamber 133. Due to the tapered structure 133, the collection chamber 135 is formed in such a way that it has a significant volume in the region of the bottom 131 within the inlet chamber 133, so that the condensate C can flow without blocking the excess part of the hydrophobic membrane. A significant amount of condensed liquid C can be collected in the inlet chamber 133 without the condensed liquid C pooling to reach the inlet opening 100. Thus, despite the accumulation of condensate C in the inlet chamber 133, the filter 1 can remain functional for extended periods of use during surgery.

Furthermore, since the inlet opening 100 extends along the vertical direction V, the line 210 can be laid closer to the filter 1 along the vertical direction V, whereby the line 210 can be laid closer to the filter 1 in a space-efficient manner. can extend towards.

Furthermore, since the inlet port 10 does not protrude significantly from the housing 13 of the filter 1, the filter 1 can be packed tightly into the package.

As can be seen from FIGS. 2 and 3 in conjunction with FIGS. 5 and 6, a support structure 142 is provided on both the housing member 14 forming the inlet side of the filter 1 and the housing member 15 forming the outlet side of the filter 1. , 152 , each support structure 142 , 152 being formed by a plurality of ridges extending transversely to the extended surface E of the hydrophobic membrane 12 . In particular, the ridges 142A, 152A are arranged to form an alternating square array such that adjacent ridges 142A, 152A allow air to pass through the gap 142B separating the ridges 142A, 152A to the extension surface E. They are separated from each other by gaps 142B and 152B so that they flow in parallel.

Support structures 142, 152 serve to support hydrophobic membrane 12 against excessive deformation. During normal operation, the hydrophobic membrane 12 is subjected to a suction force towards the outlet opening 110 and the support structure 152 on the housing member 15 forms a support for the hydrophobic membrane 12. If a reverse pressure is created, resulting in a suction force directed towards the inlet opening 100, the hydrophobic membrane 12 will now abut against the support structure 142 of the housing member 14, preventing excessive deformation in each case. (Otherwise, tearing of the hydrophobic membrane 12 will result).

As can be seen from FIGS. 2 and 6, the beam-shaped support member 153 extends across the outlet opening 110 and forms a cross structure in front of the outlet opening 110. The support member 153 extends parallel to the extension surface E and supports the membrane 12 at the outlet opening 110 and prevents the hydrophobic membrane 12 from being drawn into the outlet opening 12 so that the membrane 12 The risk of tearing at the location of the opening 110 is significantly reduced.

Because of the support structures 142, 152 and also because of the cross-shaped support member 153 at the location of the outlet opening 110, no additional measures to strengthen the hydrophobic membrane 12 may be necessary. In particular, a reinforcing layer on the hydrophobic membrane 12 to strengthen the hydrophobic membrane 12 may not be necessary, making the hydrophobic membrane 12 less expensive.

The housing parts 14, 15 are preferably formed as hard plastic parts, for example by injection molding. Here, the outlet opening 110 (having the shape of a groove) is inserted into the hydrophobic membrane 12 in order to enable the support member 153 to be formed in a position where the outlet opening 110 opens into the outlet chamber 134 . Can be tapered towards. For example, the outlet opening 110 may have a (slightly) conical shape with a narrow end 110B and a wide end 110A (see FIG. 7). This makes it possible to form the housing member 15 using a forming tool 4 comprising a recess 40 for forming the housing member 15 and a pin 41 for forming the outlet opening 110 in the outlet port 11. Become. Due to the tapered shape of the outlet opening 110, the pin 41 can be removed in the pulling direction P from the outlet opening 110 formed in the housing member 15, whereby the support member 153 can be removed using the molding tool 4. and may be formed with other portions of housing member 15 in a single molding step.

As can be seen from FIGS. 2 and 3, the filter 1 has a square shape when viewed along the extended surface E of the hydrophobic membrane 12. This further causes the inlet chamber 133 to have a significant volume close to the bottom 131 of the housing 13, allowing a significant amount of condensate C to collect within the inlet chamber 133 without interfering with the filtration process. .

In another embodiment shown in FIGS. 8 and 9, the inlet port 10 is connected to the filter 1 such that the condensate C accumulates in the inlet chamber 133 without the inlet port 10 reaching a position where it opens into the inlet chamber 133. Located near the top 132.

In the modified embodiment shown in FIG. 10, the volume of the inlet chamber 133 in the area of the bottom 131 of the housing 13 is increased, forming a collection chamber 135 in the area of the bottom 131. For this reason, the inlet chamber 133 widens toward the bottom 131 when viewed in a cross section perpendicular to the extended surface E of the hydrophobic membrane 12, and the inlet chamber 133 has a polygonal shape, as is clear from FIG. It has the shape of Since a large chamber volume is provided near the bottom 131 in the inlet chamber 133, condensate C can accumulate in the inlet chamber 133 without blocking a substantial portion of the hydrophobic membrane 12.

In another embodiment shown in FIG. 11, a collection chamber 135 can be formed above the inlet chamber 133 that extends below the lower bottom edge of the hydrophobic membrane 12. Therefore, the condensate C may accumulate in the collection chamber 135 without even reaching the hydrophobic membrane 12, so that the condensate C does not block the hydrophobic membrane 12 at all, thus affecting the filtration performance. I won't give it. The collection chamber 135 can have any desired shape, so as to ensure that a reasonably expected amount of condensate C can be collected in the collection chamber 135 over a long period of use of the filter 1. can be designed.

In the embodiment shown in FIG. 12, an additional exhaust port 16 is formed in the inlet chamber 133 near the bottom 131 of the housing 13. The condensate C is discharged through the discharge port 16 (drainage stream D) and can substantially prevent condensate C from accumulating within the inlet chamber 133.

The idea of the invention is not limited to the embodiments described above, but may be implemented in completely different ways in completely different embodiments.

Filters as described herein may be used in autotransfusion systems, but may also be used in other medical applications to filter gas flows, such as ventilators.

The filter may be used with a vacuum pump or any other type of pump that creates a negative pressure so that a gas flow is drawn through the filter.

The hydrophobic structure can be made from any suitable material and is configured to impede the flow of liquid through the hydrophobic structure, but allow gas flow, particularly air flow, to pass through. do.

The hydrophobic structure may extend in a sheet-like manner within the filter along a flat extension surface. However, it is also conceivable that the extension surface is spatially curved.

1 Filter 10 Inlet port 100 Inlet opening 11 Outlet port 110 Outlet openings 110A, 110B End 12 Hydrophobic membrane 13 Housing 130 Filter chamber 131 Bottom 132 Top 133 Inlet chamber 134 Outlet chamber 135 Collection chamber 14 Housing member 140 Connection structure 141 Clamp part 142 Support structure 142A Raised part 142B Gap 143 Tapered structure 144 Inlet structure 144A Guide surface 144B Flat surface 15 Housing member 150 Connection structure 151 Clamp part 152 Support structure 152A Raised part 152B Gap 153 Support member (cross Structure)
16 Discharge port 2 Reservoir 20 Inlet 200 Line 21 Vacuum port 210 Line 22 Housing 3 Suction pump (vacuum pump)
30 Line 4 Molding tool 40 Recess 41 Pin 5 Autotransfusion system 50 Line 51 Separation cleaning chamber 52 Line A Air flow or other gas flow C Condensate D Drainage flow E Extended surface F Liquid flow L Liquid H Horizontal direction V Vertical direction

Claims (17)

A hydrophobic filter for filtering an air stream or other gas stream in medical applications, the filter comprising:
a housing including a bottom and a top and surrounding the filter chamber;
an inlet port disposed in the housing and defining an inlet opening;
an outlet port disposed in the housing and defining an outlet opening;
a filtration medium extending from the top to the bottom of the housing and including a hydrophobic structure separating the filter chamber into an inlet chamber and an outlet chamber;
the outlet opening opens into the outlet chamber in a first position;
the inlet opening opens directly into the inlet chamber at a second position;
The second position is displaced toward the top of the housing with respect to the first position and includes a portion of the hydrophobic structure separating the inlet chamber and the outlet chamber. Hydrophobic filters arranged to face each other . The hydrophobic filter of claim 1, wherein the inlet chamber forms a collection chamber for collecting condensate at the bottom of the housing. 3. The hydrophobic filter of claim 2, wherein the inlet chamber widens towards the bottom of the housing to form the collection chamber near the bottom of the housing. 4. The hydrophobic filter of claim 3, wherein the collection chamber is displaced toward the bottom of the housing with respect to the first position. the inlet port is associated with a wall of the housing that extends generally parallel to a plane defined by the hydrophobic structure;
4. The hydrophobic filter of claim 3, wherein a portion of the collection chamber is located between the wall and the bottom of the housing. the inlet port is associated with a wall of the housing that extends generally parallel to a plane defined by the hydrophobic structure;
4. The hydrophobic filter of claim 3, wherein a portion of the collection chamber extends beyond the wall and away from the hydrophobic structure. the inlet port is associated with a wall of the housing that extends generally parallel to a plane defined by the hydrophobic structure;
a portion of the bottom of the housing extends generally perpendicular to the wall;
4. The hydrophobic filter of claim 3, wherein a portion of the collection chamber is defined by a second wall extending at an angle from the wall to the portion of the bottom of the housing. 2. The hydrophobic filter of claim 1, wherein the inlet chamber comprises an outlet for discharging condensate from the inlet chamber. the inlet chamber forms a collection chamber for collecting condensate at the bottom of the housing;
9. The hydrophobic filter of claim 8, wherein the outlet is associated with the collection chamber. 9. The hydrophobic filter of claim 8, wherein the outlet is displaced toward the bottom of the housing with respect to the first position. the outlet opening extends along a horizontal direction for guiding the air flow or other gas flow out of the filter chamber along a horizontal direction;
2. The hydrophobic filter of claim 1, wherein the inlet opening extends horizontally to guide the air flow or other gas flow horizontally into the filter chamber. 2. The hydrophobic filter of claim 1, wherein the outlet port is centrally located with respect to the hydrophobic structure. The hydrophobic filter of claim 1, wherein the outlet port and the outlet opening are substantially parallel to the inlet port and the inlet opening. The hydrophobic filter of claim 1, wherein the filter chamber has a generally square or rectangular cross-sectional shape parallel to a plane defined by the hydrophobic structure. The hydrophobic filter of claim 1, wherein the inlet opening is located directly adjacent the top of the housing. the housing includes a first housing member having the inlet port formed therein and a second housing member having the outlet port formed therein;
the first housing member includes a first clamp portion; the second housing member includes a second clamp portion;
The hydrophobic filter according to claim 1, wherein the hydrophobic structure is sandwiched between the first clamp part and the second clamp part. the first housing member includes a first support structure formed by a plurality of ridges for supporting the hydrophobic structure against deformation toward the inlet opening;
17. The second housing member comprises a second support structure formed by a plurality of ridges for supporting the hydrophobic structure against deformation toward the outlet opening. Hydrophobic filter.

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